Various devices of this type for equipping safes, vaults, or doors of protected sites are already known.
The timed control device for opening a lock described in international application published as No. W089/03922 comprises a locking mechanism controlled by an electronic device with a triggering module and a blocking module. The locking mechanism is designed to block a bolt in locked position for a predetermined time period defined by the electronic control device.
These known conventional mechanisms generally have a spring barrel and a timing mechanism with an escape device which frees the energy in a previously armed spring barrel at a moment previously defined by the timing mechanism and disengages a peg associated with a locking pin.
These timing mechanisms have the disadvantage of being very costly because the mechanical parts must be extremely precise. Furthermore, the controls which can be exerted on this type of mechanism are limited to those which can be exerted on a mechanical watch movement, in known manner.